# Sample size in genome-wide studies

How to calculate sample size needed for GWAS for a given MAF, power, $p$-value and frequency of the disease ?

• I assume GWAS is a genome-wide association study, but what is MAF? – Simon Byrne Mar 28 '11 at 13:36
• @Simon MAF stands for minor allele frequency. – chl Mar 28 '11 at 14:10